Primary Arms SLx MD-21S ACSS CQB 21mm Micro Red Dot

Description

The Primary Arms SLx MD-21S is a compact micro dot sight engineered for close-quarters applications where a fast, unobstructed sight picture matters. It features an ACSS CQB reticle and 1X power for immediate target acquisition at short ranges. The sight is designed to be lightweight yet durable, and the manufacturer notes upgraded mounting hardware for enhanced rigidity. At approximately 5 ounces, it balances weight and performance for carry and use on lightweight platforms.

Key Specifications

• This is a Red Dot sight optimized for close-quarters use.
• The reticle type is ACSS CQB for rapid engagement and target acquisition.
• The optical power is 1X for true parallax-free, both-eyes-open shooting at short range.
• The objective diameter is 21mm to provide a compact optical footprint.
• The model designation is SLx in Primary Arms’ SLx lineup.
• The external finish/color is listed as Black.
• The sight weighs approximately 5 ounces for a lightweight setup.
• The product includes upgraded mounting hardware intended to improve rigidity and repeatability.
• The category is Red Dot Sights & Non-Magnified Optics.

Compact and purpose-built, the SLx MD-21S delivers the speed and simplicity of a micro dot with rugged mounting and an ACSS CQB reticle for close-quarters scenarios. Its light weight and low profile make it a practical addition for users seeking a reliable, fast sighting option on lightweight platforms.

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